Juan Martin del Potro, who lost to Rafael Nadal in the final of Indian Wells, says he is somewhat amazed that the Spaniard could return from knee trouble after seven months off and win three of the four tournaments he’s contested.

“Of course [I’m surprised],” he said. “But I don't know how surprised I am because Rafa can do everything. Not many players can do that. He's very strong mentally. His game is very good, very strong, very solid. He has big talent, as well. His team was working with him every day to be in shape for this tournament after seven months. [But] not many players can do that. Just him or maybe one or two more in the world. But it's amazing how fast he's recovered the level.”